The present invention relates to an apparatus for pre-registering board placement generally, and more specifically an apparatus for enabling board placement to occur with minimal or no error. The present invention is particularly concerned with the fast, accurate, automated placement of boards for use in the looseleaf binder and packaging industries.
The manufacture of looseleaf binders and certain packaging products requires that boards be pre-registered in the manufacturing apparatus prior to being combined with the other elements of the binder or product. Boards are, for example, the panels that comprise a conventional three-ring binder used to hold looseleaf paper. In the process of registering the boards, three panels are used that comprise the binder: the front panel, the back panel, and the spine panel. See, for example, the method for such assembly described in U.S. Pat. No. 5,882,135. The panels are generally made of cardboard and coated with, for example, polyvinylchloride. Because of the precise measurements required of such products, the boards"" pre-registration must be within certain tolerances. For products such as looseleaf binders, the boards must be laid within a tolerance of {fraction (1/64)}th of an inch and the gap between the various boards of a single product must be as close to perfectly straight as possible.
In the past, boards had to be loaded manually, one at a time, onto a registration apparatus that ultimately produced looseleaf binders and the like. This was a slow, costly, and ineffective process. An improvement to that system came with the automation of board placement. This created a faster, more efficient way to place the boards for binding. However, these systems have a major drawbackxe2x80x94they do not produce the accuracy needed for such a precise process. Such boards cause further manufacturing problems and typically require the resulting binders to be discarded. Accordingly, there is a need for an improvement to the looseleaf board placement methods that produces efficient, high quality, pre-registered boards for successful placement.
The present invention provides an apparatus and method for pre-registering boards for use in, for example, the manufacture of looseleaf binders and packaging products. The apparatus of the present invention accurately pre-registers boards by positioning the boards placed on a base plate and securing them into place.
Initially, the boards are dropped onto the base plate by an automatic process. The present invention includes spine guides which enable the spine portion of the boards to be secured for subsequent registering. The movement of the spine guides allows the spine portion of the boards to be placed accurately. The spine guides are attached to a spine guide rack which is located on the underside of the base plate. The spine guide rack operates through the use of pneumatic cylinders and enables the movement of the attached spine guides. The spine guides move along the spine guide trench and secure boards on the base plate. The spine guides are retracted when the boards are initially placed on the base plate and then start moving medially to squeeze the spine portion of the board such that it becomes perpendicular to the x-axis. The spine guides also allow for the requisite spacing in between the spine panel and the front and back board panels. This securing apparatus which includes, among other things, the movable guide bars and spine guides, enables the placement of boards and the subsequent binding process to be within desired tolerances.
Once the spine guides have set the spine portion of the boards, the movable guide bars will begin pushing the front and back panels medially towards the y-axis. The movable guide bars will cease movement when the medial edge of the board panel comes into contact with the lateral edge of the spine guides. At this point, the movable guide bars-fixed perpendicular to the x-axis-will correct the panel positions such that the medial panel edges will achieve substantial perpendicularity with the x-axis.
Pneumatic cylinders enable the movement of the guide bars and a programmable logic controller controls the movement of the cylinders. Because rectification of the spine portion of the board by the spine guides is not sufficient for ultimate board placement accuracy, the movable guide bars further rectify the front and back board panels. The guide bars cease movement when they encounter a board that is placed onto the base plate. The pneumatic cylinders extend to a certain length and will stop moving when the boards encounter resistance. Once movement has ceased, the movable guide bars will be locked into the setup holes that are part of the base plate. This locking of the guide bars eliminates their tendency to shift and cause errors in the registration of the boards. By ceasing movement upon contact with the placed board, the guide bars secure the board in a position that enables the boards to be lifted from the base plate and subsequently placed on, for example, a revolving turntable for binding.